BLT-With-Graphics-Template/include/blt/gfx/renderer/font_renderer.h

135 lines
4.3 KiB
C++

#pragma once
/*
* Copyright (C) 2024 Brett Terpstra
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#ifndef BLT_WITH_GRAPHICS_FONT_RENDERER_H
#define BLT_WITH_GRAPHICS_FONT_RENDERER_H
#include <blt/gfx/font/font.h>
#include <blt/gfx/texture.h>
#include <blt/gfx/shader.h>
#include <blt/gfx/model.h>
#include <blt/std/hashmap.h>
#include <blt/std/binary_tree.h>
namespace blt::gfx
{
class font_texture_atlas : public texture_gl2D
{
public:
struct bounded_t
{
font::glyph_t glyph;
// starting point
blt::vec2ui min;
// ending point of the glyph, inside texture atlas
blt::vec2ui max;
};
struct added_font_results_t
{
blt::u64 last_inserted_index;
blt::u64 min_index_used;
blt::u64 max_index_used;
};
public:
explicit font_texture_atlas(blt::i32 dimensions);
added_font_results_t add_font(const font::font_file_t& file);
added_font_results_t add_font(const font::font_file_t& file, blt::u64 start);
bounded_t& get_glyph(blt::u64 c)
{ return glyphs.at(c); }
[[nodiscard]] const bounded_t& get_glyph(blt::u64 c) const
{ return glyphs.at(c); }
private:
blt::hashmap_t<blt::u64, bounded_t> glyphs;
blt::u32 used_width = 0;
blt::u32 used_height = 0;
};
class font_generator_t
{
public:
struct bounded_font_t
{
std::unique_ptr<font_texture_atlas> atlas;
float min_size, max_size;
blt::u64 min_char, max_char;
bounded_font_t(std::unique_ptr<font_texture_atlas> atlas, float minSize, float maxSize, u64 minChar, u64 maxChar):
atlas(std::move(atlas)), min_size(minSize), max_size(maxSize), min_char(minChar), max_char(maxChar)
{}
};
public:
explicit font_generator_t(blt::i32 dimensions, const std::vector<float>& sizes_to_generate);
void add_font(const font::font_file_t& file);
inline font_texture_atlas& get_texture(float size, blt::u64 c)
{
for (auto& atlas : atlases)
{
if (!(size >= atlas.min_size && size <= atlas.max_size))
continue;
if (atlas.min_char > c && atlas.max_char < c)
return *atlas.atlas;
}
throw std::runtime_error("Character not found inside atlases at this size");
}
private:
blt::i32 dimensions;
std::vector<bounded_font_t> atlases;
std::vector<float> sizes_to_generate;
};
class font_renderer_t
{
public:
struct compiled_text_t
{
std::shared_ptr<vertex_array_t> vao;
blt::size_t render_count;
};
public:
explicit font_renderer_t();
void create(const std::vector<float>& generated_font_sizes, blt::i32 dimensions = 0);
void cleanup();
void add_font(const font::font_file_t& file)
{
generator->add_font(file);
}
compiled_text_t create_text(std::string_view str);
private:
std::unique_ptr<font_generator_t> generator;
std::unique_ptr<shader_t> font_shader;
};
}
#endif //BLT_WITH_GRAPHICS_FONT_RENDERER_H